in pachi_py/pachi/tactics/1lib.c [40:50]
static inline __attribute__((always_inline)) bool
capturable_group(struct board *b, enum stone capturer, coord_t c,
enum stone to_play)
{
group_t g = group_at(b, c);
if (likely(board_at(b, c) != stone_other(capturer)
|| board_group_info(b, g).libs > 1))
return false;
return can_play_on_lib(b, g, to_play);
}